ReadableStreamDefaultReader: releaseLock() method

The releaseLock() method of the ReadableStreamDefaultReader interface releases the reader's lock on the stream.

If the associated stream is errored when the lock is released, the reader will appear errored in that same way subsequently; otherwise, the reader will appear closed.

If the reader's lock is released while it still has pending read requests then the promises returned by the reader's ReadableStreamDefaultReader.read() method are immediately rejected with a TypeError. Unread chunks remain in the stream's internal queue and can be read later by acquiring a new reader.

releaseLock()

function fetchStream() {
  const reader = stream.getReader();

  // ...

  reader.releaseLock();

  // ...
}